Blockchain-Enhanced Anonymous Data Sharing Scheme for 6G-Enabled Smart Healthcare With Distributed Key Generation and Policy Hiding

In recent years, cloud computing has seen widespread application in 6G-enabled smart healthcare, which facilitates the sharing of medical data. Before uploading medical data to cloud server (CS), numerous data sharing schemes employ attribute-based encryption (ABE) to encrypt the sensitive medical data of data owner (DO), and only provide access to data user (DU) who meet certain conditions, which leads to privacy leakage and single points of failure, etc. This paper proposes a blockchain-enhanced anonymous data sharing scheme for 6G-enabled smart healthcare with distributed key generation and policy hiding, termed BADS-ABE, which achieves secure and efficient sharing of sensitive medical data. BADS-ABE designs an anonymous authentication scheme based on Groth signature, which ensures the integrity of medical data and protects the identity privacy of DO. Meanwhile, BADS-ABE employs smart contract and Newton interpolation to achieve distributed key generation, which eliminates single point of failure due to the reliance on trusted authority (TA). Moreover, BADS-ABE achieves policy hiding and matching, which avoids the waste of decryption resources and protects the attribute privacy of DO. Finally, security analysis demonstrates that BADS-ABE meets the security requirements of a data sharing scheme for smart healthcare. Performance analysis indicates that BADS-ABE is more efficient compared with similar data sharing schemes.